Machine learning strategies for path-planning microswimmers in turbulent flows
This addresses path-planning challenges for microswimmers in turbulent environments, but it is incremental as it builds on existing reinforcement learning methods.
The paper tackles the problem of path-planning for microswimmers in turbulent flows by developing an adversarial-reinforcement learning scheme, showing it enables microswimmers to reach targets faster on average than naive approaches.
We develop an adversarial-reinforcement learning scheme for microswimmers in statistically homogeneous and isotropic turbulent fluid flows, in both two (2D) and three dimensions (3D). We show that this scheme allows microswimmers to find non-trivial paths, which enable them to reach a target on average in less time than a naive microswimmer, which tries, at any instant of time and at a given position in space, to swim in the direction of the target. We use pseudospectral direct numerical simulations (DNSs) of the 2D and 3D (incompressible) Navier-Stokes equations to obtain the turbulent flows. We then introduce passive microswimmers that try to swim along a given direction in these flows; the microswimmers do not affect the flow, but they are advected by it.